论文标题
使用可变性光谱在AGN中搜索超快速流出
Searching for Ultra-fast Outflows in AGN using Variability Spectra
论文作者
论文摘要
我们提出了定性搜索对无线电主动银核（AGN）过度变化光谱的超快速流出（UFO）的定性搜索。我们分析了Tombesi等人的42个来源。 （2010）光谱不明飞行物检测样本，以及Kara等人的另外22个不同来源。 （2016）可变性样本。共有58个来源具有来自XMM-Newton Epic-PN的足够观察数据，以及要计算的多个方差频谱的可变性。我们检查了这些光谱的峰值，与UFO的可变的蓝骨H-和HE样离子吸收线相对应。我们在28％的AGN样本中找到了这种流出的良好证据，另外31％的证据，这意味着$ \ sim $ 30-60％的AGN样品托有此类UFO。发现平均值和中位数蓝移速度分别为$ \ sim $ 0.14C和0.12C。当前的可变性方法允许对不明飞行物的快速，独立于模型的确定，但是，需要进行进一步的工作，以更好地通过更严格的建模来更好地表征这些光谱中峰的统计意义。在大量来源中检测可变的UFO线的良好证据也为吸收剂的可变性时间尺度详细分析奠定了基础。这将使我们能够探测它们的密度，并因此距离中央超级黑洞的距离。
We present a qualitative search for ultra-fast outflows (UFOs) in excess variance spectra of radio-quiet active galactic nuclei (AGN). We analyse 42 sources from the Tombesi et al. (2010) spectroscopic UFO detection sample, and an additional 22 different sources from the Kara et al. (2016) variability sample. A total of 58 sources have sufficient observational data from XMM-Newton EPIC-pn and variability for an excess variance spectrum to be calculated. We examine these spectra for peaks corresponding to variable blue-shifted H- and He-like ion absorption lines from UFOs. We find good evidence for such outflows in 28% of the AGN sample and weak evidence in a further 31%, meaning that $\sim$ 30-60% of the AGN sample hosts such UFOs. The mean and median blue-shifted velocity is found to be $\sim$ 0.14c and 0.12c, respectively. Current variability methods allow for a fast, model-independent determination of UFOs, however, further work needs to be undertaken to better characterize the statistical significance of the peaks in these spectra by more rigorous modelling. Detecting good evidence for variable UFO lines in a large number of sources also lays the groundwork for detailed analysis of the variability timescales of the absorbers. This will allow us to probe their densities and hence distances from the central super-massive black hole.
